Polar or Nonpolar Quiz
Questions: 16 · 10 minutes
1. SF₆ has six identical S–F bonds in an octahedral arrangement. What is the best classification?
Polar, because sulfur can expand its valence shell
Nonpolar, because the six bond dipoles cancel by symmetry
Nonpolar, because octahedral molecules contain no polar bonds
Polar, because S–F bonds have a large electronegativity difference
2. Which sequence correctly orders these hydrogen-halogen bonds from least polar to most polar?
H–Br, H–F, H–I, H–Cl
H–F, H–Cl, H–Br, H–I
H–Cl, H–Br, H–I, H–F
H–I, H–Br, H–Cl, H–F
3. How should the bond in an O₂ molecule be classified?
Nonpolar, because the two bonded atoms have the same electronegativity
Polar, because oxygen strongly attracts electrons
Polar, because a double bond has two dipoles
Nonpolar only when the molecule is in the gas phase
4. A student compares ethanol, which contains an O–H group, with hexane, which contains only C–C and C–H bonds. Which is expected to mix more readily with water?
Hexane, because its larger electron cloud attracts water more strongly
Both equally, because both substances contain hydrogen atoms
Ethanol, because its polar O–H region interacts favorably with water
Neither, because water mixes only with ionic compounds
5. In an H–F bond, toward which atom does the bond dipole point?
Toward the midpoint, because the electrons are shared equally
Toward hydrogen, because hydrogen has fewer electrons
Toward fluorine, because fluorine is more electronegative
Its direction alternates between hydrogen and fluorine
6. NH₃ has a trigonal pyramidal shape and three polar N–H bonds. What follows from this structure?
NH₃ is nonpolar because all three outer atoms are hydrogen
NH₃ is polar because the bond dipoles do not cancel
NH₃ is nonpolar because nitrogen's lone pair cancels every bond dipole
NH₃ is polar only after it accepts a proton
7. Formaldehyde, CH₂O, is trigonal planar around carbon and contains a strongly polar C=O bond. What is its overall polarity?
Nonpolar, because every trigonal-planar molecule has cancelling dipoles
Polar, because the C=O dipole is not cancelled by the two C–H bonds
Polar only when it forms hydrogen bonds with another substance
Nonpolar, because the two C–H bonds cancel the C=O bond exactly
8. Each C=O bond in CO₂ is polar. Why is the whole CO₂ molecule nonpolar?
Its two bond dipoles are equal and opposite in a linear molecule
Carbon and oxygen have identical electronegativities
Double bonds cannot contribute to molecular polarity
The carbon atom contains no lone pairs
9. SO₂ has polar S–O bonds and a bent molecular shape. What is its overall polarity?
Polar, because the bent geometry prevents complete dipole cancellation
Nonpolar, because the two S–O bond dipoles have equal strength
Nonpolar, because both outer atoms are oxygen
Polar only if sulfur forms an ionic bond with oxygen
10. CCl₄ has four polar C–Cl bonds arranged tetrahedrally. What is its overall molecular polarity?
Polar, because chlorine is more electronegative than carbon
Polar, because tetrahedral molecules always have a net dipole
Nonpolar, because C–Cl bonds are individually nonpolar
Nonpolar, because the symmetric bond dipoles cancel
11. A student draws the bent Lewis structure of H₂O. How should the molecule be classified?
Polar only when it is dissolved in an ionic solution
Nonpolar, because both hydrogen atoms are identical
Nonpolar, because oxygen has two lone pairs
Polar, because its O–H bond dipoles do not cancel in the bent shape
12. XeF₄ has four identical Xe–F bonds in a square planar arrangement. How should the molecule be classified?
Polar, because xenon has lone pairs
Polar, because each Xe–F bond is polar
Nonpolar, because noble-gas compounds cannot have dipoles
Nonpolar, because its square-planar bond dipoles cancel
13. BF₃ contains polar B–F bonds and has a trigonal planar geometry. How should BF₃ be classified?
Polar, because fluorine creates strong individual bond dipoles
Nonpolar, because its three symmetrically arranged bond dipoles cancel
Polar, because boron does not complete an octet
Nonpolar, because B–F bonds have no electronegativity difference
14. Which factor most directly determines whether a bond between two atoms is polar?
The electronegativity difference between the bonded atoms
The number of lone pairs anywhere in the molecule
The total number of atoms in the molecule
The physical state of the substance at room temperature
15. Consider CH₂Cl₂, a tetrahedral molecule with two hydrogen atoms and two chlorine atoms attached to carbon. Is it polar or nonpolar?
Nonpolar, because every tetrahedral molecule is symmetric
Nonpolar, because the two C–Cl dipoles cancel each other completely
Polar, because its different surrounding atoms produce a net dipole
Polar only if one of its bonds temporarily breaks
16. The cis and trans forms of 1,2-dichloroethene have the same bonds but different spatial arrangements. Which comparison is correct?
Both are nonpolar because they have the same molecular formula
Both are equally polar because bond dipoles are unaffected by geometry
The cis form is polar, while the symmetric trans form is nonpolar
The trans form is polar, while the cis form is nonpolar